Vertebral implant, vertebral fastening device of the implant and implant instrumentation

ABSTRACT

This disclosure provides vertebral implants, fastening devices for vertebral implants, and implant instrumentation, and various combinations thereof. In some embodiments, the implant comprises a peripheral wall extending according to a vertical axis between upper and lower surfaces of the implant, with each such surface configured to be placed in contact with a vertebral structure, respectively, at the top and the bottom of the vertebral segment replaced by the implant. Some embodiments comprise fastening means, deployment of which anchors the implant in the lower and upper vertebral structures. Some fastening means may be deployed by sliding parallel to the vertical axis of the implant, and may comprise a plate with at least one part remaining in contact with the peripheral wall of the implant when deployed and a pointed end projecting from one of the upper and lower surfaces of the implant to enter a vertebral structures on completion of deployment.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/891,322 having a 371(c) date of Nov. 13, 2015, and issuing as U.S.Pat. No. 9,937,050 on Jul. 10, 2018, which is a National Stage entry ofInternational Application PCT/EP2014/060135 filed May 16, 2014. Priorityis claimed under 35 U.S.C. §§ 119(a) and 365(b) to French PatentApplication No. 1354421, filed in FRANCE on May 16, 2013, through U.S.patent application Ser. No. 14/891,322 and International ApplicationPCT/EP2014/060135. U.S. patent application Ser. No. 14/891,322 andInternational Application PCT/EP2014/060135 and French PatentApplication No. 1354421 are incorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION

This disclosure relates to the field of vertebral implants, inparticular to corpectomy cages or intersomatic cages, designed toreplace a vertebral segment, that is, all or part of at least onevertebral body and/or of at least one intervertebral disc. Thedisclosure relates more particularly to a vertebral implant, inparticular to corpectomy, at least one vertebral fastening device ofsuch an implant and implant instrumentation.

TECHNOLOGICAL BACKGROUND OF THE INVENTION

A problem in the field of vertebral implants and especially ofcorpectomy cages relates to deployment of an implant capable ofreplacing a vertebral segment, sometimes large in size, at least inheight, for a corpectomy cage, since the vertebral segment cancorrespond to any or part of at least one vertebral body and/or at leastone intervertebral disc. In fact, some pathologies, especially cancerconditions, result in degradation of vertebral bodies (in part or intotality) and/or of intervertebral discs. It is necessary to replacedamaged vertebral segment(s) by an implant of considerable height. Also,it is often preferable to be able to modulate the height of the implantduring surgery, since ablation of the damaged structures generally needsdistraction of vertebrae to restore a physiological height (or lesspathological) on the treated vertebral segment and this height varies asa function of the extent of lesions (to insert the implant betweenhealthy tissues).

A problem associated with the problem of height of implants relates tothe stabilization of the implant against the vertebral structuresbetween which it is inserted. The necessary distraction is oftenincompatible with numerous stabilization solutions, such as notches onthe contact surfaces of the implant, since these notches requireadditional distraction for insertion of the implant to be made. Also,anchoring the implant is generally preferable to simple notches thatgenerally only limit the risks of movement but guarantee no reliableimmobilization.

Solutions are known from prior art, especially for corpectomy, such asexpansible cages in situ, generally comprising a body including mobileelements providing the vertebral contact surfaces and boosting theheight of the implant once the latter is inserted between the vertebrae.These solutions have disadvantages of being based on generally complexand expensive mechanisms which often embrittle the implant and/or thevertebrae, since the distraction achieved by the implant during itsexpansion often does not test the effort exerted (such that implants sagsometimes in the vertebrae). Also, they often offer reduced graft space,disallowing the addition of a bone graft or adequate substitute. Also,these solutions have a low expansion ratio (1/3) and therefore generallyrequire that the compressed implant be of a size already big enough sothat its size is satisfactory when it is expanded and the design ofthese cages often means relaxing the distraction to allow theirinsertion into the vertebral segment. Finally, these types of expansiblecages are often incompatible with notches or teeth for stabilization (asthe latter reduce the capacity of real distraction, impair positioningand risk embrittling adjacent vertebral structures) and/or withanchoring (as the cages generally do not offer a sufficiently widestructure to retain anchoring means). Also, anchoring via screws canprove fastidious to be put in place and need an excessively invasiveapproach.

A final problem, often linked to disadvantages of solutions from priorart, relates to ablation of the implant which is generally impossible ordifficult.

In this context, it is interesting to propose various embodiments for animplant that may be easily implantable, robust and reliable, adaptableto different sizes, limiting risks of embrittling adjacent vertebralstructures, offers easy ablation and anchoring in the vertebral bodieswithout compromising final positioning and without the need fordistraction superior to that required for insertion of the implant.

GENERAL DESCRIPTION OF THE INVENTION

Various embodiments of this disclosure are configured to eliminate orreduce at least one of the disadvantages of prior art disclosedhereinabove or in the art itself by proposing a vertebral implant,particularly corpectomy, which is easy to implant and fix reliably tovertebral structures adjacent to the replaced vertebral segment.

This aim is attained by a vertebral implant, for example for corpectomy,comprising at least one body of dimensions adapted to replace at leastone vertebral segment, the implant comprising a peripheral wall andextending according to a vertical axis between upper and lower surfacesof the implant each designed to be placed in contact with a vertebralstructure, respectively, at the top and the bottom of the vertebralsegment replaced by the implant, and comprising fastening means whereofdeployment enables anchoring of the implant in said lower and uppervertebral structures, each of said fastening means being deployed bysliding parallel to the vertical axis of the implant and comprising, onthe one hand, at least one plate whereof at least one part remains incontact with the peripheral wall of the implant on completion ofdeployment and, on the other hand, at least one pointed end projectingfrom one of the upper and lower surfaces of the implant to enter one ofsaid vertebral structures on completion of deployment.

This aim is also attained by a vertebral implant, in particular forcorpectomy, comprising at least one body having dimensions adapted toreplace at least one vertebral segment, the implant comprising aperipheral wall and extending according to a vertical axis between upperand lower surfaces of the implant each designed to be placed in contactwith a vertebral structure, respectively, at the top and the bottom ofthe vertebral segment replaced by the implant, further comprisingfastening means whereof deployment enables anchoring of the implant insaid lower and upper vertebral structures, each of said fastening meansbeing deployed by sliding inside the implant, according to a curvilineartrajectory, through a passage between the exterior of the peripheralwall and one of the upper or lower surfaces of the implant, andcomprising, on the one hand, at least one curved plate whereof at leastone posterior part remains inside the passage on completion ofdeployment and, on the other hand, at least one pointed end projectingfrom one of the upper and lower surfaces of the implant to enter one ofsaid vertebral structures on completion of deployment.

Also, one of the aims of some of the embodiments is to propose areliable and easy-to-use fastening device.

This aim may be attained by a vertebral fastening device for vertebralimplant, designed to be inserted, from the periphery of the spine,through a passage between the exterior of a peripheral wall of theimplant and one of the upper or lower surfaces of the implant in contactwith a vertebral structure, the device comprising a body comprising atleast one curved plate, rigid and elongated according to a longitudinalaxis extending between an anterior end and a posterior end, the platebeing configured so that its anterior end enters a vertebral structureby way of at least one pointed end while its posterior end remains inthe passage of the implant, the with the plate being on the one handcurved in the plane of the plate and having a convex lateral edge, aconcave lateral edge and two generally plane faces and, on the otherhand, being fitted with a plurality of notches arranged to engagethemselves in the wall of the passage of the implant and immobilize thefastening device in the implant when said pointed end enters saidvertebral structure.

Other particular features and advantages of the various embodiments ofthis disclosure are detailed in the following description.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

Other particular features and advantages of various embodiments of thedisclosure will emerge more clearly from the description hereinbelow,given in reference to the attached drawings, in which:

FIG. 1A shows a perspective view of an implant fitted with fasteningmeans according to some embodiments, FIGS. 1B, 1C and ID show,respectively, a profile view, a frontal view and a perspective view ofthe fastening means of FIG. 1A,

FIGS. 2A and 2B show, respectively, a frontal view and a perspectiveview of an implant fitted with fastening means according to someembodiments, FIGS. 2C and 2D show perspective views of this sameimplant, respectively, before assembly with a modular body and alone(without modular body),

FIGS. 3A and 3B show, respectively, a frontal view and a perspectiveview of an implant fitted with fastening means according to someembodiments, FIG. 3C shows a perspective view of this same implantbefore assembly with vertebral contact plates,

FIGS. 4A and 4B show, respectively, a frontal view and a perspectiveview of an implant fitted with fastening means according to someembodiments, FIG. 4C shows a perspective view of this same implantbefore assembly with two modular bodies,

FIGS. 5A and 5B show, respectively, a frontal view and a perspectiveview of an implant fitted with fastening means according to someembodiments, FIG. 5C shows a perspective view of this same implantbefore assembly with two modular bodies and FIG. 5D shows a perspectiveview of the two modular bodies assembled alone,

FIGS. 6A, 6B, 6C, 6D and 6E show perspective views of an implant fittedwith fastening means according to different embodiments,

FIGS. 7A and 7C show, respectively, a frontal view and a perspectiveview of an implant fitted with fastening means according to someembodiments, FIGS. 7D and 7F show, respectively, a frontal view and aperspective view of an implant fitted with fastening means according toother embodiments and FIGS. 7B and 7E show, respectively, a profile viewand a perspective view of the fastening means of the implants in FIGS.7A and 7C or FIGS. 7D and 7F,

FIGS. 8A and 8B show sectional views on the one hand of an implant,respectively, after and before insertion of fastening means according tosome embodiments, FIGS. 8C and 8D show sectional views on the other handof an implant, respectively, after and before insertion of fasteningmeans according to other embodiments,

FIGS. 9A, 9B, 9C and 9D show profile views of fastening means accordingto different embodiments,

FIGS. 10A and 10B show, respectively, a profile view of fastening meansand a sectional view on the one hand of an implant after pre-assembly ofthese fastening means according to some embodiments, FIGS. 10C and 10Dshow, respectively, a profile view of fastening means and a sectionalview on the other hand of an implant after pre-assembly of thesefastening means according to other embodiments,

FIGS. 11A and 11B, show, respectively, a profile view and a frontalview, of fastening means according to some embodiments, FIGS. 11C, 11Dand 11E show, respectively, a plan view from below, a profile view and aperspective view, of fastening means according to other embodiments,

FIGS. 12A and 12B, show, respectively, a profile view and a perspectiveview, of fastening means according to some embodiments, FIGS. 12C, 12Dand 12E show, respectively, a plan view from below, a profile view and aperspective view of fastening means according to other embodiments,

FIGS. 13A, 13B and 13C show, respectively, a profile view, a frontalview and a perspective view of fastening means according to someembodiments,

FIGS. 14A, 14B and 14C show, respectively, a profile view, a perspectiveview and a plan view of fastening means according to some embodiments,

FIG. 15A shows a perspective view of an implant fitted with fasteningmeans according to some embodiments, FIGS. 15B and 15C show,respectively, a frontal view and a sectional view according to thesectional plane 15C-15C of FIG. 15B, on the one hand of this sameimplant fitted with fastening means, FIGS. 15D and 15E show,respectively, a plan view from below and a perspective view of fasteningmeans according to these embodiments,

FIG. 16A shows a perspective view of an implant fitted with fasteningmeans according to some embodiments, FIGS. 16B and 16C, show,respectively, a profile view and a perspective view of the fasteningmeans according to these embodiments,

FIGS. 17A and 17B show perspective views, respectively, of an implantfitted with fastening means and fastening means alone, FIG. 17C shows aprofile view of these fastening means according to some embodiments, andFIGS. 17D and 17E show, respectively, a plan view and a perspective viewof fastening means according to other embodiments,

FIGS. 18A and 18B show, respectively, a profile view and a perspectiveview of fastening means according to some embodiments, and FIGS. 18C,18D and 18E show, respectively, a profile view, a plan view and aperspective view of fastening means according to other embodiments,

FIGS. 19A, 19B, 19C and 19D show perspective views, respectively, of animplant fitted with fastening means and fastening means alone, accordingto some embodiments, FIG. 19E shows a perspective view of a variant ofthese fastening means,

FIGS. 20A, 20B, 20C and 20D show perspective views of an implant and ofdeployment of its fastening means according to some embodiments,respectively, after deployment, on completion of deployment by means ofa spacer, before deployment by means of a stylus and on completion ofdeployment by means of a stylus of the fastening means,

FIGS. 21A, 21B, 21C and 21D show perspective views of an implant and ofdeployment of its fastening means according to some embodiments,respectively, after deployment, on completion of deployment by means ofa stylus, before deployment by means of a spacer and on completion ofdeployment by means of a spacer,

FIGS. 22A, 22B, 22C and 22D show perspective views of an implant and ofdeployment of its fastening means according to some embodiments,respectively, after deployment, before assembly, during deployment bymeans of a double stylus and on completion of deployment by means of adouble stylus,

FIGS. 23A, 23B, 23C and 23D show perspective views of an implant and ofdeployment of its fastening means according to some embodiments,respectively, after deployment, before assembly, during deployment bymeans of a spacer and on completion of deployment by means of a spacer,

FIGS. 24A and 24B show, respectively, a frontal view and a perspectiveview of an implant fitted with fastening means according to someembodiments, FIG. 24C shows this same implant during deployment of itsfastening means, FIGS. 24D and 24E show, respectively, a frontal viewand a perspective view of the fastening means of FIGS. 24A, 24B and 24C,

FIGS. 25A, 25B and 25C show perspective views of an implant and ofdeployment of its fastening means according to some embodiments, duringdeployment of the fastening means, respectively, with a double spacer, adouble stylus and an impactor, FIG. 25D shows the fastening means aloneof the embodiments of FIG. 25C,

FIGS. 26A and 26E show perspective views of an implant according to someembodiments and a spacer for insertion of these implants, FIG. 26B showsa perspective view of the implant of FIG. 26A and FIGS. 26C and 26Dshow, respectively, a profile view and a perspective view, of theinsertion spacer of the implant of FIGS. 26A and 26B,

FIGS. 27A, 27B, 27C and 27D show perspective views of an implant and ofdeployment of its fastening means according to some embodiments,respectively, after insertion of the fastening means, before deploymentduring the holding of the implant by an implant holder, duringdeployment by an impactor and after deployment,

FIGS. 28A, 28B, 28C, 28D and 28E show perspective views of an implantfitted with its fastening means and vertebral contact plates accordingto different embodiments,

FIGS. 29A, 29B and 29C show perspective views of an implant fitted withits fastening means, vertebral contact plates and vertebral adaptationtrays according to different embodiments,

FIGS. 30A and 30B show perspective views of an implant and of deploymentof its fastening means according to some embodiments, respectively,after and during deployment, FIGS. 30C and 30D show perspective views ofan implant and of deployment of its fastening means according to otherembodiments, respectively, after and during deployment,

FIG. 31A shows a perspective view of an implant fitted with fasteningmeans according to some embodiments, FIGS. 31B, 31C and 31D show,respectively, a perspective view, a profile view and a frontal view ofthe fastening means of the implant of FIG. 31A,

FIG. 32A shows a plan view of fixing means of FIGS. 31B, 31C and 31D,held by ablation pliers, FIG. 32B is an enlargement of the part 32Bdesignated by the circle of FIG. 32A.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

This disclosure relates to vertebral implants, especially for performinga corpectomy, that is, ablation of a vertebral segment and insertion ofan implant replacing the removed tissue. This disclosure also relates toat least one fastening device of implants in general, and especially(though not only) of the type specified in the present application.These fixing devices are also designated in the present application bythe terms “anchor” or “anchoring” or even “fastening means”. Thisdisclosure also relates to implant instrumentation for insertion of animplant (which may include the types described in the presentapplication) and instrumentation for fixing implants by a fasteningdevice such as those disclosed in the present application. The term“vertebral segment” is used in the present description in its acceptedform signifying “a part of the spine” since it can correspond to all orpart of at least one vertebral body and/or of at least oneintervertebral disc. In fact, corpectomy can relate to at least onewhole vertebral body, or even an entire vertebra and its adjacentintervertebral discs but can relate also to only part of a vertebralbody or several vertebral bodies, in all or part, and at least one partof at least one of the adjacent intervertebral discs. For example,especially in the case of a cancerous condition, a vertebral body can betouched only partially and advantage can be taken by preserving thehealthy part to accommodate an implant. So, various embodiments of thepresent description are configured to fix the implant in a “vertebralstructure” and this term is used in the present description in itsaccepted form signifying “at least one part of at least one elementconstituting the spine” since it can correspond to all or part of atleast one vertebral body and/or of at least one intervertebral disc. Theterms specified hereinabove and all the terms used in the presentdescription must therefore not be interpreted as limiting, and thepresent application makes it clear that it is generally a functionaldefinition that is given to the elements and characteristics described.For example, the term “vertebral implant” is used to designate the factthat the implant can relate to a vertebral segment, that is, at leastone vertebral body and/at least or an intervertebral disc. The implantcan therefore correspond to a corpectomy cage but also to anintersomatic cage, for example. Also, vertebral fixing devices, forfixing in a “vertebral structure”, can be used to fix various types ofvertebral implants, especially corpectomy cages, intersomatic cages,disc prostheses or osteosynthesis plates, etc.

The implants of some embodiments are preferably made of PEEK(polyetheretherketone) which has physical properties, especiallyrigidity, close to those of osseous tissues, and which improvespost-operative radiology follow-up (as opposed to implants made oftitanium or other metal or alloy which may create MRI flashing,aggravated by the fact that implants used for arthrodesis are oftenaccompanied by osteosynthesis plates). Fixing devices, however, arepreferably made of metal or biocompatible alloy such as titanium, toensure substantial resistance, but other materials are possible.

With respect to implantation, various methods of approach for placingthe implant are possible, even if a given method for each of the variousspinal stages is generally preferred. An anterior median mini-invasiveapproach (MIS, for Mini-Invasive Spine Surgery) for cervical vertebraeand a lateral or antero-lateral mini-invasive approach for thoracic orlumbar vertebrae could be preferred, for example (non-limiting).

Preferably, in the case of intersomatic cages or corpectomy inparticular, the implant is hollow, by way of at least one openingextending from said upper surface as far as said lower surface, as isvisible particularly on the majority of the figures non-limitinglyillustrating corpectomy cages. Such an opening of the implant betweenits surfaces in contact with vertebral structures adjacent to thereplaced vertebral segment enable insertion of cement and/or an osseousgrowth inside the implant (1) and offers a wide space of continuousgraft for adding the bone graft or the substitute to consolidate thevertebral segment operated on. The insertion of cement can also lock thevarious bodies making up the implant. Therefore, in some embodiments, asshown in the majority of the figures, the peripheral wall comprises atleast one conduit (15) to allow insertion of a graft and/or osseoussubstitute in the implant for easier osseous growth through the openingof the implant. Also, it is provided in general that the differentelements of the implant and fastening means also offer such an opening.For example, in the embodiment of FIG. 21, the fastening means plate(52) is fitted with at least one hole (53) ensuring continuity of theopening of the implant (1) as far as the vertebral structures.

In general, some embodiments preferably comprise at least one vertebralimplant (1), in particular corpectomy, comprising at least one body (10,11, 3, 3 m, 3 f) having dimensions adapted to replace at least onevertebral segment. This implant (1) generally comprises a peripheralwall and extends according to a vertical axis between the upper andlower surfaces of the implant (1) which are each designed to be placedin contact with a vertebral structure, respectively, at the top and thebottom of the vertebral segment replaced by the implant (1). Theperipheral wall preferably comprises hooking means (14, 34) for implantinstrumentation. By way of advantage, the implant (1) comprises or isassociated with fastening means (2, 2 a, 5, 8) the deployment of whichenables anchoring of the implant in said lower and upper vertebralstructures. To eliminate at least one of the disadvantages of the priorart, each of said fastening means (2, 2 a, 5, 8) is deployed by slidingalong at least one part of the implant (1). In various embodiments,these fastening means (2, 2 a, 5, 8) are deployed by sliding inside theimplant or about the periphery of the implant. Also, in variousembodiments detailed hereinbelow and which exhibit their respectiveadvantages, these fastening means (2, 2 a, 5, 8) slide according to arectilinear trajectory parallel to the vertical axis (which in turn isgenerally parallel to the axis of the spine when the implant is placedin the treated vertebral segment) or according to a curvilineartrajectory, preferably through a passage (12) between the exterior ofthe peripheral wall and one of the upper or lower surfaces of theimplant (1). Finally, as detailed hereinbelow in various advantageousembodiments, these fastening means (2, 2 a, 5, 8) preferably comprise atleast one plate (20, 52, 82,) whereof at least one part remains incontact with the implant (1) on completion of deployment to ensureproper fixing stability. Also, as detailed hereinbelow in variousadvantageous embodiments, these fastening means (2, 2 a, 5, 8) generallycomprise at least one pointed end (21, 51, 81) projecting from one ofthe upper and lower surfaces of the implant (1) to enter one of saidvertebral structures on completion of deployment. Preferably, severalpointed ends are provided to ensure better stability by way of severalfixing points. Finally, in some embodiments, those parts of thefastening means which penetrate the vertebral structures preferablycomprise portions of plates whereof the width provides resistance tomovement (of the patient which possibly have an impact on the implant)enabling good stability in the spine (better than that allowed byportions of less substantial extent, such as points or staples). Ingeneral at least one fixing means (2, 2 a, 5, 8) for each of the upperand lower vertebral structures on the treated vertebral segment isprovided, as shown in the majority of the figures, but it is possible tofix the implant only on one of these vertebral structures. Also, it isclear that fastening means can be provided according to embodiments ofthe present application that may be different for these two vertebralstructures or even at least one fixing means different from those of thepresent application. It is evident that the fastening means aregenerally rigid, for example made of metal or alloy to provided goodstability, even if the possibility of flexion of a portion of the anchoris provided in some embodiments (in this case, it is the particulararrangement which allows restricted flexion and not the material).

Implants

The implant comprises at least one body (10, 11, 3, 3 m, 3 f) havingdimensions adapted to replace the treated vertebral segment. The generalform of the implant can vary as a function of various configurations andit is not necessary to detail it as such, with the exception that itdefines a vertical axis (designated here as parallel to the axis of thespine for greater simplicity). Also, the body could have a form forimposing or correcting lordosis by way of the non-parallel upper andlower surfaces.

In some embodiments, the implant (1) comprises several bodies (10, 11,3, 3 m, 3 f) complementary to each other and stackable along thevertical axis to adapt the height of the implant (1) to the size of thevertebral segment to be replaced; this also minimizes the number ofimplants necessary to cover the whole range of possible height. Thesebodies can generally be nested together, or even locked to ensure propercohesion of the assembly. These bodies can also comprise hooking means(14, 34) for instrumentation. Various forms of bolting are possible,such as dovetails, threading and tapping, spurs, or projectionscooperating with complementary housings, etc., but it is not mandatoryto lock the bodies together if a male-female nesting is provided over asufficient height so that they do not separate during movement (from thepatient, in particular). In fact, movements have a very small range atthe vertebral level and the male and female elements, due to which twobodies fit together, only have to have dimensions (vertically) greaterthan this amplitude to ensure good stability of the assembly.

In some embodiments, illustrative and non-limiting examples of which areshown in FIGS. 2A to 2D, the implant (1) comprises a main body (10)useable alone or in combination with an additional body (11)complementary to at least one of the upper or lower surfaces of the mainbody (10), said additional body (11) comprising means (110, 111) forfitting with the main body (10) and fastening means (2, 2 a, 5, 8)sliding relative to the additional body to enter one of said vertebralstructures.

In some embodiments, illustrative and non-limiting examples of which areshown in FIGS. 3A to 3C, 4A to 4C) and 5A to 5D, the implant (1)comprises two additional bodies (3, 3 m, 3 f). In some of theseembodiments, the additional bodies (3) form trays (plateaus or endmembers) arranged on the upper and lower surfaces of the implant, forexample as shown in FIGS. 3 (A to C). In these examples, the body of theimplant comprises on its lower and upper surfaces fitting means (13) fortaking up these trays comprising complementary fitting means (33) (themale-female configuration shown in FIG. 3C can clearly be reversed).Such trays can act as anatomical adaptation elements to take the form ofvertebral structures and/or impose or correct lordosis, for example thecorrecting trays (C) shown in FIGS. 28 (A to E). Some trays (C) alsoaugment the vertebral contact surface, evident for example in FIG. 28E.These trays can for example comprise a plate (C3) fitted with a lip (C1)having dimensions adapted to accommodate the periphery of the implant,but fitting means of the type of those described hereinabove orhereinbelow can also be provided (similarly, the fitting means of theadditional bodies can be the same type as these lips). In someembodiments of these trays (C), holes (C2) are provided for passage offastening means such that vertebral anchoring is achieved by trays (C)which will be locked against the vertebral structures. Sufficiently longpointed ends (51, 21) can be provided optionally on the fastening meansto pass through the trays even at their thickest portion. Suchadditional bodies (3) can comprise at least one passage (32) for thefastening means (2, 2 a, 5, 8) of the implant, such as for exampleillustrated non-limitingly in FIG. 3C, or can comprise a structure (suchas housings (32) or passages) for taking up the fastening means, forexample illustrated non-limitingly in FIGS. 4 and 5. In someembodiments, for example as in FIG. 4C, the two additional bodies (3)are identical (which provides the advantage of limiting productioncosts) and are complementary to the main body (via the fitting means).In this way, female fitting means (31) of the additional bodies (3) forexample receive male fitting means (13) of the main body (10), or viceversa. It is evident that complementary mixed (male and female) fittingmeans can be provided to interchangeably stack several bodies on eachother. Also, in addition to the fitting means, an adequate supportsurface (133) is generally provided so that the bodies rest stably oneach other. It is also evident that the bodies, especially on theirfitting means, can comprise cutouts (130, 335) so as not to impair thefunction of other means of the implant, as evident for example in FIG.4C. In some particularly advantageous embodiments for height adaptationof the implant to the size of the treated vertebral segment, additionalbodies (3 m, 3 f) are provided, each of which can be used in combinationwith the main body (10) of the implant (1) and/or are complementary toeach other and useable alone, in combination with each other, in theabsence of a main body (10), such as for example illustrated in FIG. 5D.In such modes, as evident especially in FIG. 5C, the main body (10)comprises for example male fitting means (13) on one of its lower orupper surfaces and female fitting means on the other surface. So, anadditional body (3 m) with male fitting means (33) cooperates with thefemale fitting means of the main body (10) or the other additional body(3 f) whereof the female fitting means can also cooperate with the malefitting means (13) of the main body (10). It is therefore possible touse a single additional body (3 f) in combination with the main body(10) or two additional bodies (3 m, 3 f) together or two additionalbodies (3 m, 3 f) in combination with the main body (10). It is evidentthat the main and additional bodies illustrated in FIGS. 2 to 5illustrate the various possibilities in the case of some fastening meansbut it is clear that these illustrations are not limiting and thatvarious embodiments may use different or additional bodies. In fact, themain body can be separated (or is separable) into two, between its upperand lower surfaces, particularly between the elements which receive thefastening means, thus one or more additional bodies can be nestedbetween the two separated parts, for example by way of fitting means ofthe type of those shown in FIG. 5C.

In some embodiments, particularly advantageous when the vertebralstructures exhibit strong irregularities (for example because the entirevertebral body is not removed during surgery), the implant can compriseadditional adaptation elements (D, E), for example as illustrated inFIGS. 29 (A to C). For example, wedges (D) covering half the vertebralcontact surface or wedges (E) covering quarter of the vertebral contactsurface or any wedge covering any value of the contact surface can beadded to the implant, directly to its lower or upper surfaces, or toadaptation or correction trays (C) (as in FIGS. 29A to C), or to theadditional bodies.

Anchorings

Some embodiments, illustrative and non-limiting examples of which areshown in FIGS. 20 to 25, relate to a vertebral implant (1), inparticular for corpectomy, comprising at least one body (10, 11, 3, 3 m,3 f) having dimensions adapted to replace at least one vertebralsegment, the implant (1) comprising a peripheral wall and extendingaccording to a vertical axis between the upper and lower surfaces of theimplant (1) each designed to be placed in contact with a vertebralstructure, respectively, at the top and the bottom of the vertebralsegment replaced by the implant (1). This type of implant comprisesfastening means (5, 8) deployment of which enables anchoring of theimplant in said lower and upper vertebral structures, each of saidfastening means (5, 8) being deployed by sliding parallel to thevertical axis of the implant (1). These fastening means (5, 8) comprise,on the one hand, at least one plate (52, 82) whereof at least one partremains in contact with the implant (1) on completion of deployment and,on the other hand, at least one pointed end (51, 81) projecting from oneof the upper and lower surfaces of the implant (1) to enter one of saidvertebral structures on completion of deployment.

In some of these embodiments, illustrative and non-limiting examples ofwhich are shown in FIGS. 20 and 21, the fastening means (5) slide insidethe peripheral wall of the implant (1), parallel to the vertical axis.For example, in some embodiments shown in FIGS. 20 (A to D) said plate(52) of the fastening means (5) is arranged, inside the implant, in aplane perpendicular to the vertical axis and is fitted with at least onepoint (51) oriented according to the vertical axis. This type ofanchoring is for example inserted in the implant (1), perpendicularly tothe vertical axis, via at least one housing (56) in the peripheral wallof the implant (1), said housing (56) having a width complementary tothe width of the plate (52) and a height at least equal to that of thefastening means (5). This housing (56) terminates at one of the lower orupper surfaces of the implant (1) via at least one hole receiving saidpoint (51) such that the latter penetrates one of said vertebralstructures through this hole in the lower or upper surface. In general,several points (51) are provided, four points for example as shown inFIGS. 20 (A, B and D). The plate (52) has a generally rectangular formfor example on which the points (51) are arranged, perpendicularly tothe plane of the plate (52). The plate is guided in vertical translationinside the housing (56) during deployment. At least one fixing means (5)is provided in general for each of the upper and lower vertebralstructures on the treated vertebral segment. This deployment can becarried out, as shown for example by way of illustration in FIG. 20B, bymeans of a spacer (6) whereof the branches (65) are each inserted intoone of the two upper and lower housings (56) of the implant (1) to pushon the two fastening means at the same time. This deployment can also becarried out, as shown for example by way of illustration in FIGS. 20Cand 20D, by means of at least one stylus (7) whereof an end (75) tapersprogressively, such that when it is inserted further into the housing(56), it pushes the plate (52) in the direction of the vertebralstructure towards which the pointed end (51) of the fastening means (5)points. This type of use of the spacer (6) and of the stylus (7) is thesame for numerous embodiments of the fastening means and it will not bedetailed again for the other modes, since it is clear that those ofordinary skills in the art will appreciate the operation and the use ofthese tools or instruments in the various embodiments described in thepresent application. In another example, especially such as someembodiments shown in FIGS. 21 (A to D), said plate (52) of the fasteningmeans (5) is arranged in a plane perpendicular to the vertical axis,fitted with at least one point (51) oriented according to the verticalaxis and inserted in the implant (1), parallel to the vertical axis, viaat least one housing in one of the upper and lower surfaces of theimplant (1). The periphery of said plate (52) remains in contact withthe walls of this housing when said point (51) enters one of saidvertebral structures to stabilize the assembly, the plate (52) and thehousing of the implant (1) having complementary shapes, as evidentespecially in FIG. 21A. It is evident that the forms illustrated areillustrative and that various forms can be selected, of course. Theplate (52) preferably comprises a hole (53) providing continuity withthe opening passing through the implant for osseous growth, if need be.Fasteners or locks may be provided so as to avoid any movements of thefixation/fastening means (5) when deployed. Such fasteners or locks maycomprise various mechanisms such as snap-fit studs, sliding pins, tenonand mortise, etc.

In some embodiments, illustrative and non-limiting examples of which areshown in FIGS. 22 to 25, the fastening means (5, 8) slide around theperipheral wall of the implant (1), parallel to the vertical axis. Forexample, said plate (52, 82) of the fastening means (5, 8) comprises atleast one hole (53) having dimensions at least equal to those of theperiphery of the implant (1) and forming a crown arranged in a planeperpendicular to the vertical axis and sliding around the peripheralwall the implant (1), parallel to this vertical axis. Blocking means(16, 17, 18, 54) limiting the sliding of said plate (52, 82) aregenerally provided so that the plate (52, 82) remains in contact withthe peripheral wall of the implant (1) when said pointed end (51, 81)penetrates one of said vertebral structures. In some of theseembodiments, illustrative and non-limiting examples of which are shownin FIGS. 22 (A to D), 23 (A to D) and 30 (C and D), said blocking means(16, 17, 54) limiting the sliding of said plate (52) comprise, on theone hand, a groove (54) in the wall of the hole (53) of said plate (52)and a groove (16) in the peripheral wall, in the region of at least oneof the lower and upper surfaces of the implant (1), and, on the otherhand, a slotted ring (17) which fits into the two grooves (16, 54),similarly to a clamping clip, to block the plate (52) relative to theimplant (1) when said pointed end (51) penetrates one of said vertebralstructures. It is evident that the slotted ring can comprise fingers oreyelets to make its placement on the groove (16) of the implant easier.An access housing (54) to the ring, especially its fingers or eyelets,can also be provided in the plate (52) to facilitate ablation. In otherembodiments, illustrative and non-limiting examples of which are shownin FIGS. 24 (A to E), 25 (A to D) and 30 (A and B), said blocking means(18) limiting the sliding of said plate (52, 82) comprise a crown (18)mounted in the region of at least one of the lower and upper surfaces ofthe implant (1) to block the plate (52, 82) relative to the implant (1)when said pointed end (51, 81) penetrates one of said vertebralstructures through at least one hole (195, 188) in said crown (18).

In some embodiments, illustrative and non-limiting examples of which areshown in FIGS. 22 (A to D), 23 (A to D) and 30 (A to D), said plate (52)which slides about the implant is fitted with at least one straight andvertical point (51) forming said pointed end penetrating one of saidvertebral structures. In other embodiments, illustrative andnon-limiting examples of which are shown in FIGS. 24 (A to E) and 25 (Ato D), the sliding plate (82) is fitted with at least one helicoidalplate (80) fitted with at least one point (81), forming said pointed endpenetrating one of said vertebral structures via vertical slidingaccompanied by rotation, according to a helicoidal movement. Thehelicoidal plate (80) fitted with at least one point (81) is oftendesignated hereinbelow by the term “helicoidal point (81)” forsimplicity but it is clear that this is preferably a pointed plate eventhough it can simply be a pointed rod. In some of these embodiments,deployment of the fastening means (5, 8) can be carried out by means ofa spacer (6) as described previously, preferably a spacer (6) withdouble branches whereof both branches (66, 68) pass on either side ofthe peripheral wall, for example as in FIG. 23C, 23D or 25A. In some ofthese embodiments, deployment of the fastening means (5, 8) can becarried out by means of a stylus (7) as described previously, preferablya stylus (7) with double branches whereof both branches (76, 78) pass oneither side of the peripheral wall and are supported for example to pushsaid sliding plate (52, 82), on a bead (19) projecting on the peripheryof the peripheral wall between the upper and lower surfaces (for examplehalfway), for example as in FIG. 22C, 22D or 25B. It is evident thatsuch a bead can in fact be an additional body interposed between twoportions bearing the fastening means, similarly to the explanationsupplied earlier in the present application. In some embodiments,illustrative and non-limiting examples of which are shown in FIGS. 25Cand 25D, the sliding plate (82) with helicoidal points (81) comprises,on its face opposite that fitted with the points, notches, teeth orcrenellations (83) configured so that a tool (88) comprising an end ofform complementary to these notches (83) can be used to anchor thehelicoidal points in the vertebral structures. In fact, in the case ofan osseous structure, it is often necessary to proceed by “impingement”,that is, by striking on a tool transmitting the shocks to the fasteningmeans. In this way, by successively using the various notches (83) ofthe plate (82) it is possible to aid translation and especially rotationof the plate, necessary for penetration of the helicoidal points in thevertebral structures.

It is evident in the embodiments described hereinabove that the points(51, 81), even if they are often illustrated by a sharpened cylindricalelement (resembling a nail), are preferably formed by sharpened plateswhich offer better stability in the bone. Preferably, when severalpoints (51, 81) in the form of a plate are used for the same vertebralstructure, the plane of these plates will be oriented not parallelrelative to each other (for example perpendicularly) such that thevertebral fixing is opposed optimally to movements in severaldirections.

It is also evident that various embodiments allow the fastening means tobe pre-mounted on the implants for easier preparation of implantationduring surgery.

As detailed earlier in the present application, some embodiments relateto fastening means inserted according to a curvilinear trajectory and/oran implant comprising such fastening means. Such a trajectory isadvantageous since it anchors the implant by using the same method ofapproach as that used for insertion of the implant in the treatedvertebral segment and therefore allows easier access for impingement offastening means in the vertebrae, especially according to an approachaxis perpendicular to the axis of the spine (at least approximately).So, some embodiments relate to a vertebral implant (1), in particularfor corpectomy, comprising at least one body (10, 11, 3, 3 m, 3 f)having dimensions adapted to replace at least one vertebral segment, theimplant (1) comprising a peripheral wall and extending according to avertical axis between the upper and lower surfaces of the implant (1),each designed to be placed in contact with a vertebral structure,respectively, at the top and the bottom of the vertebral segmentreplaced by the implant (1). This implant comprises fastening means (2,2 a, 2 d) deployment of which enables anchoring of the implant in saidlower and upper vertebral structures, each of said fastening means (2, 2a, 2 d) being deployed by sliding inside the implant (1), according to acurvilinear trajectory, via a conduit or passage (12) between theexterior of the peripheral wall and one of the upper or lower surfacesof the implant (1). These fastening means (2, 2 a, 2 d) comprise, on theone hand, at least one curved plate (20) whereof at least one posteriorpart remains inside the passage (12) on completion of deployment and, onthe other hand, at least one pointed end (21) projecting from one of theupper and lower surfaces of the implant (1) to enter one of saidvertebral structures on completion of deployment. This curved plate (20)is preferably curved in the plane defined by the plate and thereforegenerally has a convex lateral edge, a concave lateral edge and twogenerally plane faces, as is generally visible in the majority offigures. All the same, in some embodiments, illustrative andnon-limiting examples of which are shown in FIGS. 17, 18 and 19, thecurve of the plate is not in the plane defined by the plate since itdoes not define a plane, but in contrast, the plate is arched andtherefore has a concave face, a convex face and two straight lateraledges. Also, in some embodiments, illustrative and non-limiting examplesof which are shown in FIGS. 7B and 7E, the plate is curved in bothdirections at the same time and therefore has a concave edge, a concaveface (24), a convex edge and a convex face (25). This double curveorients the anchoring in various directions as needed, as can be seenparticularly in FIGS. 7A and 7C or in FIGS. 7D and 7F.

In these embodiments, the implant is therefore linked to fastening meanswhich are used after insertion of the implant, as opposed to theembodiments described hereinabove. Such fastening means forming anarched plate only need for the implant to have one passage (12) such asdescribed. In this way, this disclosure also relates to just thefastening device. In some embodiments, this disclosure therefore relatesto a vertebral fixing device (2, 2 a, 2 d) for vertebral implant (1),designed to be inserted, from the periphery of the spine, through aconduit or passage (12) between the exterior of a peripheral wall of theimplant and one of the upper or lower surfaces of the implant (1) incontact with a vertebral structure, the device (2, 2 a, 2 d) comprisinga body comprising at least one curved plate (20), rigid and elongatedaccording to a longitudinal axis extending between an anterior end and aposterior end (23, 23 a, 23 d), the plate (20) being configured so thatits anterior end enters a vertebral structure by way of at least onepointed end (21) while its posterior end (23, 23 a, 23 d) remains in thepassage (12) of the implant (1). This fixing device (2, 2 a, 2 d) ispreferably configured with a plate (20) which is curved in the plane ofthe plate and has a convex lateral edge, a concave lateral edge and twogenerally plane faces. Also, the plate (20) of this device (2, 2 a, 2 d)is preferably fitted with a plurality of notches (27) arranged to fit inthe wall of the passage (12) of the implant (1) and immobilize thefastening device (2, 2 a, 2 d) in the implant (1) when said pointed endenters said vertebral structure.

The embodiments described hereinbelow also refer to the implantcomprising the anchor in the form of a curved plate as the anchoritself, hereinbelow sometimes designated by the term “arched plate”. Aposterior part of the arched plate remains in the implant and this partmust be adequate to fit well in the implant. The posterior end (23, 23a, 23 d) is preferably in the implant also, flush with the entry of thepassage or at least without exceeding the peripheral wall too much,which would risk damaging surrounding tissues. In some embodiments, saidcurved plate (20) is arranged in a vertical plane inside the passage(12) of the implant (1) and the curve of the plate (20) is oriented inthis vertical plane. The passage therefore has a generally rectangularsection (optionally with rounded edges) with a width at least equal tothe thickness of the arched plate (20) and a length (or height since itis vertical) at least approximately equal to the width of the archedplate (20). The arched plate has an approximately constant width overits entire posterior portion designed to remain in the implant but canbe slightly wider at its posterior end to allow blockage in the passage.Such blockage can also be obtained by thickening of the plate at itsposterior end, or by a stop. The length of the arched plate (20),between its posterior end and its anterior pointed end (“anterior” and“posterior” being defined in reference to the direction of insertion ofthe plate in the implant) depends on the length of the passage, thepositioning and/or orientation of the passage (12) relative to the upperor lower surface of the implant (such as for example evident in thevarious variants illustrated in FIGS. 6A, 6B, 6C, 6D and 6E) and of theradius of curvature of the plate which is adapted to the trajectorydefined by the passage, but this length could also vary as a function ofthe depth at which the pointed end is to enter the vertebral structuresand optionally the presence of trays (3, C) or other anatomicaladaptation elements. In this way, in some embodiments, the length ofsaid plate (20) and of said points (21) is configured as a function ofthe passage such that just the two points project from the implant andpenetrate the vertebral structures. Also, this concerns radius ofcurvature and it is clear that the edges or curved faces of the platedescribe one or more radii of curvature. Finally, the passage (12)imposes a curvilinear trajectory on the anchor (2, 2 a, 2 d) but it inturn can be curved, as illustrated for example in FIGS. 8C and 8D, orrectilinear. When it is rectilinear, it preferably comprises at leasttwo rectilinear portions of different orientations (tangential to aradius of curvature which the plate is to follow), as illustrated forexample in FIGS. 8A and 8B. This type of passage in 2 rectilinearportions makes it easier to manufacture the implant by rectilinear bores(one from the passage inlet and one from the outlet), and facilitatespassage of the anchor.

In some embodiments, at least one posterior portion of the curved plate(20) comprises a plurality of notches (27) engaging in the wall of thepassage (12) of the implant (1) to immobilize the fastening means (2, 2a, 2 d) on completion of deployment. Such notches or teeth (27) blockthe arched plate in the passage. In some embodiments, these notches (27)become anchored in a wall of the passage, especially in the case of aPEEK implant and enable immobilization of the plate in the implant (inthe direction in which the anchor is removed and optionally also in thedirection of the penetrated vertebral structures). These notches can beprovided on the concave edge but preferably on the convex edge whichprovides better support, as illustrated for example in FIGS. 11 (A toE), 12 (A, C and D) and 8C, and/or on at least one of the plane faces,as illustrated for example in FIGS. 13 (A to C), 14 (A to C) where thenotches are on both faces and 15 (B to E). In other embodiments, thesenotches (27) can be provided on at least one part of the concave face,but preferably the convex face, as illustrated for example in FIG. 17 (Bto E), 18 (A to E) or 19C and 19D. In some embodiments, said curvedplate (20) comprises, on at least one posterior portion, a slot (29)passing through its entire thickness for disengaging said notches (27)during removal of the fastening means (2, 2 a, 2 d). This type ofarrangement has the advantage of facilitating ablation. According to theposition of the notches (27), the slot will be positioned to allowflexion of at least one of the branches separated by the slot (29) todisengage the notches (27). FIGS. 11D, 11E, 12A, 12B, 12D and 12E showexamples of such slots. FIGS. 13A and 13C show other examples in whichthe two branches separated by the slot are not in the same plane: thebranch bearing the notches is curved in the direction of the notches,for better gripping of the notches (27) in the wall of the passage (12)of the implant. Pushing this branch in the opposite directionfacilitates removal. FIGS. 15 (A to E) also show a variant in which noslot is provided, but where the notches (27) are present over a portionof the plate which is curved in the direction of the notches. Pushing(twisting) this posterior portion of the plate, for example by way of atool penetrating a housing (290) provided for this purpose via access(129) provided in the wall of the passage (12) facilitates ablation. Itis noted that this type of ablation housing (290) can be provided invarious places, as a function of the position of the notches, asillustrated for example in FIG. 12C. Similarly, FIGS. 12A and 12B showtwo housings (290) of this type optionally allowing them to be grippedby pliers to bring the two branches towards each other. FIGS. 17D and17E show another variant of non-coplanar branches where action on atleast one of the branches disengages the anchor. FIGS. 18D and 18E showyet another variant where the slot (29) traverses the thickness of theplate but in a plane not perpendicular to the plate such that the slotis oblique in the thickness of the implant. In this way, by clamping thetwo branches (bringing them towards each other), one of them on whichthe notches (27) will be provided will straddle the other and free upthe notches (27). FIGS. 31 (A to D) and 32 (A and B) show yet anothervariant where the slot (29) separates the curved plate (20) into twobranches which bear notches (27) on their external rectilinear lateraledges (located at the side oppose the slot). This type of arrangementdisengages the notches (27) by bringing the two branches towards eachother, for example by means of piers gripping the anchor at the level ofergots arranged at the posterior end, for example as shown in FIGS. 32Aand 32B.

In some embodiments, said curved plate (20) comprises, in the region ofits posterior end, at least one stop surface (28) not parallel to thesurface of the plate to limit penetration of the fastening means (2, 2a, 2 d) in the implant (1). FIGS. 11 (C to E), 12 (A to E), 17 and 18show illustrative examples of such stops.

In some embodiments, said pointed end (21) comprises two points (21)separated by at least one sharp portion (22) (e.g., a cutting portion)facilitating penetration in the vertebral structures. Such a sharpportion can also be provided on various edges of the anchor, preferablyonly on the part designed to penetrate the vertebral structures. Forexample, FIGS. 9A and 9B show sharp portions (22) on several edges ofthe plate (20). Similarly, in FIGS. 9C and 9D where the anchor has onepoint (21) only, sharp edges (22) facilitate insertion of the anchor. Itis evident that the points of the same plate (20) cannot have the samelength, such that one of them exits from the implant before the other,for example as illustrated in FIGS. 10C and 10D (by comparison withFIGS. 10A and 10B).

In some embodiments, said curved plate (20) comprises, on an anteriorportion designed to penetrate the vertebral structures, a plurality ofteeth (26), notches or indentations to improve retention of the anchorin the penetrated tissues. FIGS. 9D, 19E, 31B, 31C and 31D showillustrative and non-limiting examples of such teeth (26).

In some embodiments, illustrative and non-limiting examples of which areshown in FIGS. 19 (A to E) and 16 (A to C), the fastening means (2 a, 2d) with a curved plate in fact comprise several curved plates joined bya link (23 a, 23 d), for example, such as a plate or a stickperpendicular to the planes of the curved plates, optionally withirregularities in form (234) to match other elements of the implant.This type of arrangement multiplies the anchoring points and benefitsfrom the advantage given by the plate form offering better stabilitythan narrower structures. It is evident in the figures that the twocurved plates are parallel to each other, but that they could beprovided not parallel, i.e. even perpendicular to optimize resistance tomovement once planted in the vertebral structures.

The foregoing shows that various embodiments, in particular for theanchors with arched plates, permits numerous variants and that theexamples provided are illustrative only and that the terms used todefine the characteristics must not be interpreted as limiting butrather in their functional definition. Also, the present disclosuredetails several embodiments of the fastening or anchoring means but alsoconcern any combination thereof. In particular, in some embodiments, itis useful to use at least two fastening means for each of the vertebralstructure between which the implant is intended to be inserted. Thepresent disclosure thus also concerns a fastening system for implantscomprising at least two fastening means. More specifically, in the caseof corpectomy, it is useful to have such fixation by more than onefastening or anchoring mean, because several physiological structureshave been removed from the patient and a better stabilization preferablyhas to be achieved. Such stabilization is obtained by a combination ofat least two fastening means as described in the present disclosure foreach vertebral structure. It should be noted that one fastening means ofthe present disclosure could be combined with any other known fasteningmeans, such as screws or any other device, although it will be preferredto combine two anchoring means as in the present disclosure. FIGS. 30Aand 30C show two illustrative and non-limiting examples of suchcombination. Furthermore, the (at least) two fastening means can eitherbe identical or different from each other and may have orientationsparallel to each other or not. A non-parallel orientation generally isuseful for a better stabilization and the fastening means can also havedifferent length so that their part protruding from the implant andpenetrating the vertebral structures are offset from each other, so asto further improve the stabilization.

Instrumentation

This disclosure also relates to instrumentation for insertion of theimplant and/or impingement of the fastening means.

In some embodiments, illustrative and non-limiting examples of which areshown in FIGS. 27 (A to D), instrumentation comprises an implant holder(P) which preferably cooperates with the hooking means (14) provided onthe implant. These means can be housings or any type of structure forthe implant to be held by the instrument. On the other hand,instrumentation can comprise at least one impactor (I) for havinganchors with a curved plate penetrate the vertebral structures.Advantageously, the implant holder (P) and the impactor (I) arecomplementary to each other such that the implant holder (P) holding theimplant allows, or even guides, the sliding of the impactor, for exampleas shown in FIGS. 27C and 27D. For example, the implant holder maycomprise a head (P2) bordered by at least one wing (P1) on which canrest at least one branch of the impactor guided in this way towards theimplant. Advantageously, the impactor (I) can comprise at least twobranches (12) for impacting at least two anchors through the implant atthe same time, for example on either side of the head (P2) of theimplant holder (P) which provides a reliable guide rail.

According to various embodiments, the instrumentation can comprise atleast one distractor (or distraction clamp) on the one hand to at leastmaintain or even enlarge (even if distractors with big contact surfaceare generally preferred) the space left by the removed vertebralsegment, and, on the other hand facilitate placement of the implant (1).FIGS. 26A, 26C and 26D show an example of a distractor (9 b) comprisinga plate (90) having a surface (900) configured to receive and guide theimplant to the implant space (between the vertebral structures), forexample by means of branches (91) supporting the vertebral structuresand forming rails along which shoulders (19 b) of the implant areguided, for example as shown in FIG. 26B. FIG. 26E shows another exampleof a distractor (9 b) comprising a branch supporting the vertebralstructures and forming a rail along which the implant is guided, forexample by way of grooves (19 b) on its upper and lower surfaces. Thesetypes of spacers facilitate implantation and enable insertion of theimplant, especially with an implant holder (P), in particular of thetype of those described in the present application, and even the use ofan impactor (1), a spacer (6) or a stylus (7) as described in thepresent application. This disclosure therefore also relates toinstrumentation comprising all or part of these various tools orinstruments.

At least in some embodiments described in the present application, it isevident that the arrangement of the fastening means, the implant and theinstrumentation fix the implant by means of at least two fastening meansin the vertebral structures located above and below (in the spine) thevertebral segment replaced by the implant. In fact, by means of a doubleimpactor or two impactors (1) sliding above and below an implant holder(P), it is possible especially via configuration of various embodimentsof the anchors of the present application to anchor at least two anchorsat the same time, in the same vertebral structure or each in one of theupper and lower structures on the treated vertebral segment, because thetrajectories of these anchors, even when they are curvilinear, do notcross and the configuration of the implant (especially the footprint) iscompatible with such simultaneous anchoring of the two anchors.

The present application describes various technical characteristics andadvantages in reference to the figures and/or embodiments. The expertwill know that the technical characteristics of a given embodiment canin fact be combined with characteristics of another embodiment unlessotherwise stipulated or it is evident that these characteristics areincompatible or the combination does not supply a solution to at leastone of the problems technical mentioned in the present application.Also, the technical characteristics described in a given embodiment canbe isolated from the other characteristics of this mode unless otherwisestipulated. In this way, for example, FIGS. 30A, 30B, 30C and 30D showcombinations of fastening means of various embodiments on the sameimplant. FIGS. 30A and 30B show for example a plate (52) sliding aboutthe implant and comprising points (51) which pass through holes (195) ofa locking crown (18) of the sliding and arched plates (20) which arethen inserted and preferably slightly project from the peripheral wallof the implant to lock the sliding plate (52) against the crown (18),ensuring complete blocking of the points (52) in the vertebralstructures. FIGS. 30C and 30D show other examples of combination inwhich the sliding plate (52) (locked by clamping clip) actually forms athick crown comprising passages arranged for taking up arched plates(20). Once the points (51) of the sliding plate (52) are planted in thevertebral structures, the arched plates are added to reinforce thefixing.

It must be evident for the person skilled in the art that thisdisclosure permits embodiments in numerous other specific forms withoutdeparting from the field of application of this disclosure.Consequently, the present embodiments must be considered by way ofillustration, but can be modified in the field defined by the scope ofthe attached claims, and the claims based on this disclosure must not belimited to the details given hereinabove.

The invention claimed is:
 1. A corpectomy cage and anchor for treating aspine comprising an upper housing, a medial housing, and a lowerhousing, and further comprising: an upper surface on the upper housingconfigured to contact a lower surface of an upper segment of the spine;a lower surface on the upper housing having a dovetailed recess; aperipheral wall disposed between the upper surface of the upper housingand the lower surface of the upper housing; and a passage extending fromthe peripheral wall of the upper housing to the upper surface of theupper housing; a lower surface on the lower housing configured tocontact an upper surface of a lower segment of the spine; an uppersurface on the lower housing having a dovetailed recess; a peripheralwall disposed between the upper surface of the lower housing and thelower surface of the lower housing; and a passage extending from theperipheral wall of the lower housing to the lower surface of the lowerhousing; a dovetailed projection extending along the upper surface ofthe medial housing configured to interlock with the dovetailed recess ofthe upper housing; a dovetailed projection extending along the lowersurface of the medial housing configured to interlock with thedovetailed recess of the lower housing; and a peripheral wall disposedbetween the upper surface of the medial housing and the lower surface ofthe medial housing; an upper anchor comprising an upper anchor bodycomprising a pair of opposing generally planar external surfaces and apair of opposing curvilinear external surfaces, with an upper one of thepair of curvilinear surfaces being concave and a lower one of the pairof curvilinear surfaces being convex; a sharpened projection extendingfrom a leading end of the upper anchor body; and a stop surfaceprotruding from a trailing end of the upper anchor body; and a loweranchor comprising a lower anchor body comprising a pair of opposinggenerally planar external surfaces and a pair of opposing curvilinearexternal surfaces, with a lower one of the pair of curvilinear surfacesbeing concave and an upper one of the pair of curvilinear surfaces beingconvex; a sharpened projection extending from a leading end of the loweranchor body; and a stop surface protruding from a trailing end of thelower anchor body.
 2. The corpectomy cage of claim 1, wherein at leastone of the upper anchor and the lower anchor include a plurality ofpointed ends separated by the sharpened projection.
 3. The corpectomycage of claim 1, wherein at least one of the upper anchor and the loweranchor include a pointed end oriented according to a vertical axis ofthe corpectomy cage upon insertion into the passage.
 4. The corpectomycage of claim 1, wherein the passage in the upper housing has acurvilinear trajectory extending between the peripheral wall and theupper surface.
 5. The corpectomy cage of claim 1, wherein at least oneof the upper anchor and the lower anchor include a plurality of teeth,notches, or indentations to improve retention of the anchor in apenetrated tissue.
 6. The corpectomy cage of claim 1, wherein at leastone of the upper anchor and the lower anchor include a plurality ofteeth arranged to engage a wall of the passage and secure it therein. 7.A corpectomy cage comprising: an upper housing including: an uppervertebral contact surface configured to contact a first vertebral body,a upper connecting surface including a upper dovetailed recess, an upperperipheral wall disposed between the upper vertebral contact surface andthe upper connecting surface, and an upper passage extending from theupper peripheral wall to the upper vertebral contact surface; a lowerhousing including: a lower vertebral contact surface configured tocontact a second vertebral body, a lower connecting surface including alower dovetailed recess, a lower peripheral wall disposed between thelower vertebral contact surface and the lower connecting surface, and alower passage extending from the upper peripheral wall to the uppervertebral contact surface; a medial housing including an upperdovetailed projection extending along an upper surface to interlock withthe upper dovetailed recess on the upper housing and a lower dovetailedprojection extending along a lower surface to interlock with the lowerdovetailed recess on the lower housing; a curved upper anchor includinga sharpened projection extending from a leading end and a stop surfaceprotruding from a trailing end, the curved upper anchor adapted toextend through the upper passage and engage the first vertebral body;and a curved lower anchor including a sharpened projection extendingfrom a leading end and a stop surface protruding from a trailing end,the curved lower anchor adapted to extend through the lower passage andengage the second vertebral body.
 8. The corpectomy cage of claim 7,wherein at least one of the upper anchor and the lower anchor include aplurality of pointed ends separated by the sharpened projection.
 9. Thecorpectomy cage of claim 7, wherein at least one of the upper anchor andthe lower anchor include a pointed end oriented according to a verticalaxis of the corpectomy cage upon insertion into either the upper passageor the lower passage.
 10. The corpectomy cage of claim 7, wherein atleast one of: the upper passage has a curvilinear trajectory extendingbetween the upper peripheral wall and the upper vertebral surface; andthe lower passage has a curvilinear trajectory extending between thelower peripheral wall and the lower vertebral surface.
 11. Thecorpectomy cage of claim 7, wherein at least one of the upper anchor thelower anchor include a plurality of teeth, notches, or indentations toimprove retention of the anchor in a penetrated tissue.
 12. Thecorpectomy cage of claim 7, wherein at least one of the upper anchor andthe lower anchor include a plurality of teeth arranged to engage a wallof either the upper passage or the lower passage and secure it therein.13. A spinal implant assembly comprising: an implant including avertebral contact surface, a peripheral enclosing a hollow core, and apassage comprising an interior wall and extending from the peripheralwall to the vertebral contact surface; and an anchor comprising a bodywith a shape complementary to the shape of the passage and a pluralityof teeth disposed on a surface of the anchor, wherein upon insertion ofthe anchor into the passage at least one tooth of the plurality of teethincludes a tip engaging the interior wall and securing the anchor withinthe passage.
 14. The spinal implant assembly of claim 13, wherein thepassage includes a curvilinear trajectory extending between theperipheral wall and the vertebral contact surface.
 15. The spinalimplant assembly of claim 13, wherein the anchor includes a tissueengaging portion comprising at least one pointed end.
 16. The spinalimplant assembly of claim 15, wherein the tissue engaging portionincludes a plurality of teeth, notches, or indentations to improveretention of the anchor in a penetrated tissue.
 17. The spinal implantassembly of claim 15, wherein the tissue engaging portion includes acutting portion disposed between two pointed ends.
 18. The spinalimplant assembly of claim 13, wherein the passage includes a rectilineartrajectory extending between the peripheral wall and the vertebralcontact surface.
 19. The spinal implant assembly of claim 13, whereinthe implant includes a second passage comprising a second interior walland extending from the peripheral wall to the vertebral contact surface;and wherein the anchor includes a second body with a shape complementaryto the shape of the second passage and a second plurality of teethdisposed on a surface of the second body, wherein upon insertion of thesecond body into the second passage at least one tooth of the secondplurality of teeth includes a tip engaging the second interior wall andsecuring the anchor within the passage and the second passage.
 20. Thespinal implant assembly of claim 19, wherein the anchor includes a linkjoining the body and the second body adjacent a first end, and whereinthe link engages a portion of the peripheral wall upon insertion of theanchor into the implant.